Hi Reda
A bit late for a reply but I found your post recently and it helped me to solve a similar problem, so I wanted to share one possible solution.
On 21 January 2012 23:19, Reda Aouad reda.aouad@gmail.com wrote:
After endless tests, I tried to replace record_route_preset with insert_hf, writing the complete record route headers. A light started to come out of the tunnel.....
Suppose User A is registered to port 53, User B to port 5060.
In the case of double record route, when A sends an INVITE to B, I write the following in the SIP header of the INVITE forwarded to B : Record-Route: sip:public_ip:5060;r2=on;lr=on Record-Route: sip:public_ip:53;r2=on;lr=on
The first transaction, INVITE / 200OK goes well, with Kamailio forwarding packets correctly from the corresponding socket of each user.
The problem arises when User B sends BYE to the 5060 port, with both route headers in the SIP header of the BYE. I get the following error : WARNING: rr [loose.c:747]: no socket found for match second RR
after which Kamailio forwards the BYE from the 5060 socket to User A. User A being registered on port 53, ignores the packet coming with source port 5060. The BYE is never replied to.
I guess that means that Kamailio is not able to find the private_ip:53 socket from the public_ip:53 record-route header. I hope it was clear.
One way to get around this is to populate the RR with a hostname instead of an address. Then you can configure it so that the external clients resolve public_ip but the Kamailio server itself resolves private_ip. This can be done through an entry in /etc/hosts to override the public DNS entry.
Not exactly elegant but it works for me.
I think there's a fundamental issue with running Kamailio behind NAT and listening on multiple port numbers. Am I the only one suffering from this type of configuration?
(Part of the problem is also tied to dumb ALG NAT routers which try to out-smart SIP servers, without which I wouldn't run Kamailio on multiple ports, and life would be much easier)
Regards, Richard